Currently, SDN networks provide multicast packet switching mainly by converting packets into multicast broadcast frames and propagating them to all available administrative network ports. This leads to excessive replication of traffic and imposes limitations on the ability of a network to scale when there is a large number of users.
In software-defined networks, network management and data transfer layers are separated by delegating management functions (performed by routers, switches, etc.) to applications running on a separate server (controller). The idea of such networks was suggested by specialists of Stanford and Berkeley Universities in 2006, and the studies initiated by them found support not only among academicians, but were also embraced by the leading manufacturers of network equipment, who in March 2011, founded the Open Networking Foundation (ONF) consortium. Its founders were Google, Deutsche Telekom, Facebook, Microsoft, Verizon and Yahoo.
IT companies are interested in SDN because such technologies can give a 25-30% improvement of network equipment performance, a 30% reduction of network operating costs, streamline network management, ensure better security and provide users with the ability to programmatically create new services and quickly upload them to the network's hardware.
Patent document US20130322443A1 “SDN Facilitated Multicast in Data Center” (patentee: Futurewei Technologies, Inc., published on May 12, 2013) describes a method that requires a dedicated multicast controller, with this controller is used to transport traffic to virtual machines and designed for use in data centers only, which are significant drawbacks.
Currently, in SDN networks, packet multicasting using IPv4 protocol is mostly carried out by converting them into broadcast frames and propagating them to all available administrative network ports. This leads to excessive replication of traffic and imposes limitations on the ability of a network to scale when there is a large number of users.